US4297149A - Method of treating SiPOS passivated high voltage semiconductor device - Google Patents
Method of treating SiPOS passivated high voltage semiconductor device Download PDFInfo
- Publication number
- US4297149A US4297149A US06/146,380 US14638080A US4297149A US 4297149 A US4297149 A US 4297149A US 14638080 A US14638080 A US 14638080A US 4297149 A US4297149 A US 4297149A
- Authority
- US
- United States
- Prior art keywords
- devices
- annealing
- temperature
- breakdown voltage
- sipos
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000004065 semiconductor Substances 0.000 title claims abstract description 12
- 238000000034 method Methods 0.000 title claims description 11
- 230000015556 catabolic process Effects 0.000 claims abstract description 27
- 238000000137 annealing Methods 0.000 claims abstract description 15
- 238000001465 metallisation Methods 0.000 claims abstract description 10
- 229910052751 metal Inorganic materials 0.000 claims abstract description 3
- 239000002184 metal Substances 0.000 claims abstract description 3
- 238000002161 passivation Methods 0.000 claims description 10
- 229910021420 polycrystalline silicon Inorganic materials 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 4
- 238000005275 alloying Methods 0.000 abstract description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 4
- 239000001301 oxygen Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 229910052782 aluminium Inorganic materials 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 238000006731 degradation reaction Methods 0.000 description 2
- 238000000151 deposition Methods 0.000 description 2
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 description 1
- 239000012080 ambient air Substances 0.000 description 1
- 230000001668 ameliorated effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/324—Thermal treatment for modifying the properties of semiconductor bodies, e.g. annealing, sintering
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/30—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26
- H01L21/31—Treatment of semiconductor bodies using processes or apparatus not provided for in groups H01L21/20 - H01L21/26 to form insulating layers thereon, e.g. for masking or by using photolithographic techniques; After treatment of these layers; Selection of materials for these layers
- H01L21/3105—After-treatment
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S257/00—Active solid-state devices, e.g. transistors, solid-state diodes
- Y10S257/905—Plural dram cells share common contact or common trench
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S438/00—Semiconductor device manufacturing: process
- Y10S438/958—Passivation layer
Definitions
- This invention relates to the field of passivation of high voltage semiconductor devices.
- This problem is ameliorated by annealing the devices at a temperature above 525° C. prior to metallization and by alloying the metallization at a temperature of less than 425° C. for less than ten minutes above 400° C. Full voltage capability is recovered by annealing at above 550° C. prior to metallization.
- SiPOS oxygen doped polycrystalline silicon
- the devices are subsequently metallized with aluminum and were alloyed in a tube furnace set at 450° C.
- the resulting finished devices had subsequently lower breakdown voltages than expected.
- the cause of the problem was not understood because it was assumed that the metal alloying temperatures were low enough that they would not affect a SiPOS layer which had been annealed at 900° C.
- subsequent experimentation established that the maximum breakdown voltage is obtained by minimizing the time the devices spend in the 400° C. to 525° C. temperature range following the SiPOS anneal.
- the device breakdown voltage does degrade in the 400° C. to 425° C. temperature range, but significant degradation does not accumulate until after more than ten minutes total time in this range.
- a device of this type whose breakdown voltage has decreased to 1300 volts will recover 90 to 95% of its original breakdown voltage if it is annealed at 525° C. for one-half hour.
- Such a device (1300 v breakdown) annealed at 550° C. for one-half hour will recover its full initial 1700 volt breakdown voltage.
- the maximum breakdown voltage is provided by avoiding permitting the devices to soak in the 400°-525° C. temperature range subsequent to SiPOS anneal or by annealing the devices at above 550° C. prior to metallization if they have been permitted to sit in a 400°-525° C. environment.
- This anneal is carried out in a tube furnace set at 550° C.
- the devices are pulled directly from the furnace to ambient air in order that they will cool rapidly through the 525° C.-400° C. temperature range.
- the devices are then metallized with aluminum or other appropriate metallization and the metallization is alloyed in a belt furnace with its peak temperature set at less than 425° C. for a maximum time of ten minutes above 400° C.
- the resulting devices have substantially their entire 1700 volt breakdown voltage.
- the annealing at 550° C. is preferably utilized as a pre-metallization treatment to assure that devices will have maximum breakdown voltage even if through some error, oversight, or furnace loading effects in previous steps they have soaked in the forbidden temperature range at some point subsequent to the SiPOS anneal.
- Subsequent steps which make an annealing advisable include the fusing of a glass overcoat over the SiPOS junction passivation under conditions which may result in excessive soaking in the 400° C. to 525° C. temperature range.
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Internal Circuitry In Semiconductor Integrated Circuit Devices (AREA)
- Electrodes Of Semiconductors (AREA)
- Formation Of Insulating Films (AREA)
Abstract
The breakdown voltage of high voltage semiconductor devices passivated with SiPOS deteriorates if the devices are allowed to soak at temperatures in the 400° C. to 525° C. range. The original breakdown voltage is recovered by annealing the devices at a temperature of above about 550° C. prior to metallization and alloying the metal at less than 425° C.
Description
1. Field of the Invention
This invention relates to the field of passivation of high voltage semiconductor devices.
2. Prior art
Many passivation techniques have been utilized in prior art high voltage semiconductor devices. Passivation of the high voltage junction by depositing an oxygen doped polycrystalline silicon layer on the surface of the device bridging the junction has become a popular way to passivate semiconductor devices. For integrated circuits and other low voltage devices this is proved to be an effective passivation technique. As a result it has been used for the passivation of high voltage semiconductor devices.
3. The problem
In attempting to apply oxygen doped polycrystalline silicon as a passivation technique to high voltage semiconductor devices such as deflection transistors which have a design breakdown voltage of 1700 volts, we have discovered that the breakdown voltage of these devices is dependent on the thermal history of the device. We have found that allowing the devices to sit at 450° C. for as little as ten minutes will decrease the breakdown voltage by as much as 200 volts. Longer times will produce greater degradation of the breakdown voltage. We have determined that the primary range of temperature sensitivity for our devices is in the 400° C. to 525° C. range and that the most rapid deterioration occurs in the range of 450° C. to 500° C.
This problem is ameliorated by annealing the devices at a temperature above 525° C. prior to metallization and by alloying the metallization at a temperature of less than 425° C. for less than ten minutes above 400° C. Full voltage capability is recovered by annealing at above 550° C. prior to metallization.
Our 1700 volt breakdown voltage devices use depletion moats at the high voltage junction. The oxygen doped polycrystalline silicon (SiPOS) passivation layers on these devices are about 5500 Angstroms thick and are deposited at about 600° C. from source gases comprising about 20% N2 O and about 80% SiH4. This SiPOS layer is deposited directly on the semiconductor surface. Subsequent to its deposition the SiPOS layer is annealed at 900° C. for from one-half hour to one hour.
The devices are subsequently metallized with aluminum and were alloyed in a tube furnace set at 450° C. The resulting finished devices had subsequently lower breakdown voltages than expected. Initially the cause of the problem was not understood because it was assumed that the metal alloying temperatures were low enough that they would not affect a SiPOS layer which had been annealed at 900° C. However, subsequent experimentation established that the maximum breakdown voltage is obtained by minimizing the time the devices spend in the 400° C. to 525° C. temperature range following the SiPOS anneal.
The device breakdown voltage does degrade in the 400° C. to 425° C. temperature range, but significant degradation does not accumulate until after more than ten minutes total time in this range.
If a device having an initial breakdown voltage of 1700 volts is allowed to soak at 450° C. for ten minutes the breakdown voltage will reduce to about 1500 volts. Continued exposure to this temperature results in continuing reduction in the breakdown voltage with an asymptote of about 800 volts.
It is thought that the decrease in breakdown voltage may be a result of changes in the types of oxygen-silicon bonds present in the oxygen doped polycrystalline silicon.
A device of this type whose breakdown voltage has decreased to 1300 volts will recover 90 to 95% of its original breakdown voltage if it is annealed at 525° C. for one-half hour. Such a device (1300 v breakdown) annealed at 550° C. for one-half hour will recover its full initial 1700 volt breakdown voltage.
We have found that the maximum breakdown voltage is provided by avoiding permitting the devices to soak in the 400°-525° C. temperature range subsequent to SiPOS anneal or by annealing the devices at above 550° C. prior to metallization if they have been permitted to sit in a 400°-525° C. environment. This anneal is carried out in a tube furnace set at 550° C. At the end of the annealing time, the devices are pulled directly from the furnace to ambient air in order that they will cool rapidly through the 525° C.-400° C. temperature range. The devices are then metallized with aluminum or other appropriate metallization and the metallization is alloyed in a belt furnace with its peak temperature set at less than 425° C. for a maximum time of ten minutes above 400° C. The resulting devices have substantially their entire 1700 volt breakdown voltage.
The annealing at 550° C. is preferably utilized as a pre-metallization treatment to assure that devices will have maximum breakdown voltage even if through some error, oversight, or furnace loading effects in previous steps they have soaked in the forbidden temperature range at some point subsequent to the SiPOS anneal. When cooling the devices at the end of the SiPOS anneal it is preferred to cool them slowly to 550° C. and then rapidly through the problem temperature range. This substantially minimizes the problem of breakdown voltage loss in the event that subsequent high temperature steps are not performed.
Subsequent steps which make an annealing advisable include the fusing of a glass overcoat over the SiPOS junction passivation under conditions which may result in excessive soaking in the 400° C. to 525° C. temperature range.
A processing technique for obtaining maximum breakdown voltage for semiconductor devices which are passivated with SiPOS has been described. Those skilled in the art will be able to modify the preferred embodiment in view of the teachings of the specification without departing from the spirit of the invention as defined in appended claims.
Claims (6)
1. In a process of fabricating a semiconductor device having oxygenated polycrystalline silicon passivation layers the improvement comprising:
annealing the devices at at least 525° C. prior to metallization;
cooling the devices rapidly through the 500° C. to 450° C. temperature range at the end of said annealing;
preventing the devices from subsequently being heated to any temperature higher than 425° C.; and
preventing the devices from being exposed to any temperature above 400° C. for longer than a total of ten minutes subsequent to the annealing whereby the devices will have near the maximum breakdown voltage of which their structure is capable.
2. The method recited in claim 1 wherein:
said annealing step is performed at a temperature of at least 550° C.
3. The method recited in claim 1 wherein:
said annealing step is carried out for a period of at least one-half hour.
4. The method recited in claim 1 wherein subsequent to metal deposition:
the metal is alloyed with the semiconductor at a temperature in the range between 400° C. and 425° C.
5. The method recited in claim 1 wherein:
said rapid cooling is through the 525° C. to 400° C. temperature range.
6. A method of maximizing the breakdown voltage of semiconductor devices having oxygenated polycrystalline silicon passivation layers comprising:
annealing said devices at a temperature above 525° C. prior to metallizing the devices;
cooling said devices rapidly through the temperature range 525° C. to 425° C. following said annealing;
preventing said devices from being heated to above 425° C. subsequent to said annealing.
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/146,380 US4297149A (en) | 1980-05-05 | 1980-05-05 | Method of treating SiPOS passivated high voltage semiconductor device |
IT20995/81A IT1137677B (en) | 1980-05-05 | 1981-04-08 | HIGH VOLTAGE SEMICONDUCTIVE DEVICE, PASSIVATED WITH A LAYER OF POLYCRYSTALLINE SILICON DROUGHT WITH OXYGEN |
SE8102651A SE8102651L (en) | 1980-05-05 | 1981-04-27 | SEMICONDUCTOR DEVICE |
YU01089/81A YU108981A (en) | 1980-05-05 | 1981-04-27 | Method of making semiconductor devices |
DE19813116998 DE3116998A1 (en) | 1980-05-05 | 1981-04-29 | "METHOD FOR PRODUCING A SEMICONDUCTOR COMPONENT" |
JP6680881A JPS572529A (en) | 1980-05-05 | 1981-04-30 | Method of manufacturing high voltage semiconductor device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/146,380 US4297149A (en) | 1980-05-05 | 1980-05-05 | Method of treating SiPOS passivated high voltage semiconductor device |
Publications (1)
Publication Number | Publication Date |
---|---|
US4297149A true US4297149A (en) | 1981-10-27 |
Family
ID=22517112
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US06/146,380 Expired - Lifetime US4297149A (en) | 1980-05-05 | 1980-05-05 | Method of treating SiPOS passivated high voltage semiconductor device |
Country Status (6)
Country | Link |
---|---|
US (1) | US4297149A (en) |
JP (1) | JPS572529A (en) |
DE (1) | DE3116998A1 (en) |
IT (1) | IT1137677B (en) |
SE (1) | SE8102651L (en) |
YU (1) | YU108981A (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4349408A (en) * | 1981-03-26 | 1982-09-14 | Rca Corporation | Method of depositing a refractory metal on a semiconductor substrate |
US4516145A (en) * | 1983-08-31 | 1985-05-07 | Storage Technology Partners | Reduction of contact resistance in CMOS integrated circuit chips and the product thereof |
US4580156A (en) * | 1983-12-30 | 1986-04-01 | At&T Bell Laboratories | Structured resistive field shields for low-leakage high voltage devices |
USH665H (en) | 1987-10-19 | 1989-08-01 | Bell Telephone Laboratories, Incorporated | Resistive field shields for high voltage devices |
US5374843A (en) * | 1991-05-06 | 1994-12-20 | Silinconix, Inc. | Lightly-doped drain MOSFET with improved breakdown characteristics |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE300472B (en) * | 1965-03-31 | 1968-04-29 | Asea Ab | |
US3674995A (en) * | 1970-08-31 | 1972-07-04 | Texas Instruments Inc | Computer controlled device testing and subsequent arbitrary adjustment of device characteristics |
US3971061A (en) * | 1973-05-19 | 1976-07-20 | Sony Corporation | Semiconductor device with a high breakdown voltage characteristic |
US4001873A (en) * | 1973-12-26 | 1977-01-04 | Mitsubishi Denki Kabushiki Kaisha | Semiconductor device |
-
1980
- 1980-05-05 US US06/146,380 patent/US4297149A/en not_active Expired - Lifetime
-
1981
- 1981-04-08 IT IT20995/81A patent/IT1137677B/en active
- 1981-04-27 SE SE8102651A patent/SE8102651L/en not_active Application Discontinuation
- 1981-04-27 YU YU01089/81A patent/YU108981A/en unknown
- 1981-04-29 DE DE19813116998 patent/DE3116998A1/en not_active Withdrawn
- 1981-04-30 JP JP6680881A patent/JPS572529A/en active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE300472B (en) * | 1965-03-31 | 1968-04-29 | Asea Ab | |
US3674995A (en) * | 1970-08-31 | 1972-07-04 | Texas Instruments Inc | Computer controlled device testing and subsequent arbitrary adjustment of device characteristics |
US3971061A (en) * | 1973-05-19 | 1976-07-20 | Sony Corporation | Semiconductor device with a high breakdown voltage characteristic |
US4001873A (en) * | 1973-12-26 | 1977-01-04 | Mitsubishi Denki Kabushiki Kaisha | Semiconductor device |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4349408A (en) * | 1981-03-26 | 1982-09-14 | Rca Corporation | Method of depositing a refractory metal on a semiconductor substrate |
US4516145A (en) * | 1983-08-31 | 1985-05-07 | Storage Technology Partners | Reduction of contact resistance in CMOS integrated circuit chips and the product thereof |
US4580156A (en) * | 1983-12-30 | 1986-04-01 | At&T Bell Laboratories | Structured resistive field shields for low-leakage high voltage devices |
USH665H (en) | 1987-10-19 | 1989-08-01 | Bell Telephone Laboratories, Incorporated | Resistive field shields for high voltage devices |
US5374843A (en) * | 1991-05-06 | 1994-12-20 | Silinconix, Inc. | Lightly-doped drain MOSFET with improved breakdown characteristics |
Also Published As
Publication number | Publication date |
---|---|
IT8120995A0 (en) | 1981-04-08 |
IT1137677B (en) | 1986-09-10 |
IT8120995A1 (en) | 1982-10-08 |
SE8102651L (en) | 1981-11-06 |
DE3116998A1 (en) | 1982-02-04 |
JPS572529A (en) | 1982-01-07 |
YU108981A (en) | 1983-09-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
Nissan-Cohen et al. | The effect of hydrogen on trap generation, positive charge trapping, and time-dependent dielectric breakdown of gate oxides | |
US7569502B2 (en) | Method of forming a silicon oxynitride layer | |
JPH04299566A (en) | Method for maintaining resistance value of polycrystalline silicon for high resistance | |
US4134125A (en) | Passivation of metallized semiconductor substrates | |
US6017806A (en) | Method to enhance deuterium anneal/implant to reduce channel-hot carrier degradation | |
EP0170848B1 (en) | Thermal annealing of integrated circuits | |
KR20050035285A (en) | Nitrogen passivation of interface states in io2/sic structures | |
US20060205159A1 (en) | Method of forming gate flash memory device | |
US4297149A (en) | Method of treating SiPOS passivated high voltage semiconductor device | |
US3988181A (en) | Method of doping a polycrystalline silicon layer | |
JPH0218934A (en) | Manufacture of semiconductor device | |
US6737367B1 (en) | UV-supported thermal treatment of compound semiconductors in RTP systems | |
JPH0787187B2 (en) | Method for manufacturing GaAs compound semiconductor substrate | |
KR100715860B1 (en) | High Pressure Hydrogen Annealing for MOSFET | |
JP2794708B2 (en) | Method for reducing stored charge in semiconductor device | |
JPH10223628A (en) | Manufacture of semiconductor device | |
KR970052802A (en) | Method of forming interlayer insulating film of semiconductor device | |
JPH03196619A (en) | Formation of copper wire and target used therefor | |
US6440829B1 (en) | N-profile engineering at the poly/gate oxide and gate oxide/SI interfaces through NH3 annealing of a layered poly/amorphous-silicon structure | |
US20010034090A1 (en) | Methods for forming a gate dielectric film of a semiconductor device | |
US6674151B1 (en) | Deuterium passivated semiconductor device having enhanced immunity to hot carrier effects | |
KR0137550B1 (en) | Formation method of gate oxide | |
KR100358128B1 (en) | Method for forming gate electrode | |
KR0162900B1 (en) | Ramped oxide formation method | |
JPS6142911A (en) | Forming method of conductive layer by implanting ion |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
AS | Assignment |
Owner name: INTERSIL CORPORATION, FLORIDA Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:HARRIS SEMICONDUCTOR PATENTS, INC.;REEL/FRAME:010247/0161 Effective date: 19990813 |
|
AS | Assignment |
Owner name: CREDIT SUISSE FIRST BOSTON, AS COLLATERAL AGENT, N Free format text: SECURITY INTEREST;ASSIGNOR:INTERSIL CORPORATION;REEL/FRAME:010351/0410 Effective date: 19990813 |